A fluid fitting assembly can comprise a receiving member, a fitting member, and a seal member. The receiving member has a body (e.g., a block or tubular structure) and a port formed therein which communicates with a volume of pressurized fluid. In an inexpensive port design (e.g., SAE J1926 and/or ISO 6149), the port includes an internal thread section and a chamfer section between a port-surrounding surface of the body and the thread section. A standard (and low cost) fitting member comprises a head and a shank having an external thread section and an undercut section between the head and the thread section. When the fitting member is coupled to the receiving member (i.e., the respective thread sections are screwed together), the chamfer section of the receiving member and the undercut section of the fitting member form a chamber within the port. The seal member (i.e., an elastomeric O-ring) is squeezed into this chamber to seal the interface between the receiving member and the fitting member.